拆分 main 功能模块

Co-Authored-By: Claude <noreply@anthropic.com>

stream/sse.go

@@ -0,0 +1,29 @@
+package stream
+
+import (
+	"encoding/json"
+	"fmt"
+	"io"
+)
+
+type Frame struct {
+	Type    string         `json:"type"`
+	Text    string         `json:"text,omitempty"`
+	Message string         `json:"message,omitempty"`
+	Tool    string         `json:"tool,omitempty"`
+	Stage   string         `json:"stage,omitempty"`
+	Status  string         `json:"status,omitempty"`
+	Data    map[string]any `json:"data,omitempty"`
+	Stats   *Stats         `json:"stats,omitempty"`
+	Error   string         `json:"error,omitempty"`
+}
+
+type EmitFunc func(Frame)
+
+func WriteSSEJSON(w io.Writer, frame Frame) {
+	data, err := json.Marshal(frame)
+	if err != nil {
+		data, _ = json.Marshal(Frame{Type: "error", Error: "序列化流事件失败"})
+	}
+	fmt.Fprintf(w, "data: %s\n\n", data)
+}